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Photos of Algal Blooms

Despite their name, blue-green algae can be a variety of colors. Blooms can be blue, green, brown, white or a combination of colors. Do you want to share a picture of blue-green algae from your local lake?  Email photos with a description of the bloom and the location to


Blue-Green Algae

A green paint-like algal bloom


Blue-Green Algae Tainter Lake

An algal scum on Tainter Lake in Dunn County during the summer of 2010.


Blue-Green Algae

A decaying algal mat on Lake Kegonsa in Dane County during June of 2010.




Blue-Green Algae Fox Lake

A multi-colored algal bloom on Fox Lake in Dodge County.



Blooms on Lake Chetac in Sawyer County in July 2014.

Report blue-green algae related illnesses to the Wisconsin Harmful Algal Bloom Program by calling 608-266-1120.
Last revised August 7, 2023